Disk harrow



Aug. 16, 1932. E. c. BOPF DISK HARROW Filed Oct. 31, 1931 2 Sheets-Sheet l INV EN TOR.

WITNESS.

E. C. BOPF Aug. 16, 1932.

DISK HARROW Filed 001:. 31, 1931 2 Sheets-Sheet 2 WlTNESS.

Patented Aug. 16, 1932 UNITED STATES PATENT OFFICE EDWARD C. 30191, OF IOLINE, ILLINOIS, ASSIG-NOB TO DEERE & COMPANY, 01 MOLINE, ILLINOIS, A CORPORATION OF ILLINOIS DISK HABBOW Application filed October 31, 1981. Serial No. 572,248.

My invention relates to disk harrows and particularly to the two gang tandem if-set type. This type of harrow is used 1n cultivating orchards and is off-set laterally from the tractor so as to pass beneath the overhanging branches of the trees.

One of the objects of the invention is to provide an improved angle adjusting member between the front and rear gangs which is so constructed that the draft stress therein is always in tension irrespective of the angle of the gangs or the contour of the ground over which the harrow is operated, and irrespective of whether a pulling force or a backward thrust is applied to the harrow. An advantage of this arrangement is that a much lighter construction may be used for the angle adjusting member than if this member needed to withstand compression stresses.

Another object of the invention is to provide an angle adjusting member which permits the gangs to freely turn into a reverse angle from a transport position, to facilitate the making of a right hand turn, without placing the adjusting member in compression.

Other objects and advantages of my 1nvention will be apparent to those skilled in the art after a consideration of the following detailed description, taken in conjunction with the accompanying drawings wherein:

Fig. 1 is a plan view of a conventional tandem ofi'set disk harrow illustrating my improved angle adjusting member adjusted for transporting Fig. 2 is a plan View showing the position of the parts when the harrow is turned to the ri ht;

Fig. 3 is a plan View of the disk harrow showing the gangs angled to an operating position;

Fig. 4 is an enlarged inverted detail view of the arouate angle adjusting member and the associated frame members of the front and rear gangs;

Fig. 5 is an enlarged detail view taken on the plane of line 5-5 of Fig. 1; and,

Fig. 6 is an enlarged detail view taken on the plane of line 6-6 of Fig. 1.

The disk harrow comprises the usual front gang 8 and rear gang 9 having disk supporting frames 11 and 12, respectively. ,The frame 11 of the front gang comprises a pair of transversely disposed parallel angle iron bars 13 and 14. Angle iron bars and 16 are secured to the ends of the transverse bars 13 and 14 and serve to hold these bars in spaced parallel relation. The rear ends of the bars 15 and 16 converge rearwardly at 17 and 18 and are secured to a vertical sleeve or pivot member (not shown). An angle iron bar 19 extends forwardly from the pivot member and is secured to the bars 13 and 14. An angle iron bar 20 is arranged parallel with the bar 19 and is also secured to the bars 13 and 14 and to the converging'bar 17. A pair of disk gangs are disposed in axial alignment between the transverse bars 13 and 14 and are supported at their adjacent inner ends by the angle iron bars 19 and 20, and at their outer ends by bars 15 and 16. Hitch bars converge forwardlyfrom the ends of the transverse bar 13 and are adapted to engage the drawbar of a tractor. The frame 12 of the rear gang 9 comprises a rearwardly extending U-shaped angle iron member 21 and a transverse angle iron bar 22-is secured to the ends thereof. Spaced parallel angle iron bars 23 extend between the members 21 and 22 and support the inner ends of the axially aligned rear disk gangs, the outer ends of the gangs being supported on the U-shaped member 21. A pivot bracket 24 comprising a pair of vertically spaced perforated arms is secured to the member 21 and extends forwardly therefrom. A pivot bolt 25 passing through the perforations in the arms of bracket 24, and through the sleeve located at the converged ends of the bars 17 and 18, connects the front and rear gangs.

The front and rear gangs are held in any ,one of a number of angular positions by -means of an arcuate shaped angle adjusting member 35. Member 35 is supported from the rear gang by a bracket 31 which is secured to the frame member 21, at one side of the pivot bracket 24, by means of bolts 32. A pin or bolt 33 is provided in the bracket 31 which extends through aslot 34 formed adjacent one end of member 35. A slot 36 is provided in the opposite end of the member 35 and a bolt 37 extends through this slot and through the frame member 21. Member 35 extends forwardly from the frame member 21 of the rear gang and is supported in stirrups 38 secured to the under side of the frame bars 18 and 19 of the front gang. A roller 39 is also supported in each stirrup 38 and serves as a rolling contact for theinner edge of adjusting member 35. A bracket 41, best shown in Fig. 5, is secured to the angle iron frame bars 17 and 20 and a roller 42 is supported in this bracket and contacts with the inner edge of the arcuate angle adjusting member 35. The rollers 39 and 42 form a three pointrolling contact between adjusting member 35 and the frame 11 of the front gang 8.

A locking pin 43 is supported in the bracket 41 and is adapted to selectively engage holes 44 provided in the adjusting member 35. A lever 45 is pivotally mounted on the bracket 41 and one end of the lever engages the locking pin 43. A rope or cable may be secured to the opposite end of the lever 45 and extend forwardly to the operators seat on the tractor. A spring 46 is slipped over the pin 43 and is interposed between the lever 45 and a plate 47 which is formed on the bracket 41 and serves to normally hold the pin 43 in engagement with one of the holes 44. A slot 48 is provided in angle adjusting member 35 and the pin 43 extends into this slot when the disk gangs are straightened for transport.

When the disk harrow is being transported the gangs 8 and 9 are straightened, as shown in Fig. 1, so that the disks run in a longitudinally straight line and the pin 43 is positioned in the slot 48. To angle the disk gangs into an operating or cutting position the operator pulls on the lever 45 thereby lifting the pin 43 out of the slot 48. The tractor is then backed, forcing the disk gangs to angle, un til the pin 43 registers with a selected one of the holes 44 whereupon the lever 45 is re leased so as to permit the pin to drop into the hole. In Fig. 3 the disk gangs are shown in the extreme angled osition with the pin 43 engaging the last ho e 44.

In the operation of the disk harrow the front and rear gangs are set at the desired angle and are locked in this position by means of the pin 43 engaging one of theholes in adjusting member 35. Under normal operating conditions when pulling straight ahead, draft is transmitted to the rear gang through pivot bolt 25, as well as through pin 43, bolt 33, and that portion of member 35 between pin 43 and bolt 33. The latter portion of member 35 is stressed in tension, and the remaining portion thereof is under no stress.

Under load, the strain in the portion of member 35 under stress and in the members comprising the frame may permit a slight degree of counter-clockwise rotation of the rear frame about bolt 25, but this will merely cause a movement of bolt 37 forwardly in the slot 36 and therefore cannot place that portion of member 35 between pin 43 and bolt 37 under compression stress. \Vhen making a sharp left hand turn, or under circumstances in which substantially all the load on the rear gang is thrown on the extreme right hand end thereof, the rear gang tends to rotate about bolt 25 in a clockwise direction. This causes bolt 37 to move to the end of slot 36, and thereafter places the normally inactive portion of member 35 in tension, and relieves the portion between pin 43 and bolt 33. The latter is not placed under compression because bolt 33 is free to move forwardly in slot 34.

It follows then that under no condition of load, can any portion of member 35 be stressed in compression. Either the portion between pin 43 and bolt 33 is under tension, and the remaining portion is under no stress, or the latter portion is under tension and the portion between pin 43 and bolt 33 is under no stress.

It will also be apparent from the foregoing that a compression stress is not present in member 35 whether the implement is in transport or operating position, or whether it is drawn forwardly or backed. By reason of the absence of a compression stress in member 35 at all times, this member may be made of lighter material thereby reducing the cost of construction.

In transporting, the gangs are held in a parallel position by pin 43 bearing against the rear end of the elongated slot 48, the natural tendency of the rear gang being to swing clockwise when traveling straight forward or when turning left. When turning right, the presence of the slot permits the gangs to go into a reverse angle which facilitates the making of a turn in this direction.

While I have described in connection with the accompanying drawings the specific form in which I prefer to embody my invention, it is to be understood that the invention is not to be limited to the specific means which I have herein shown and described, and that, in fact, widely different means may be employed in the practice of the broader aspects of my invention.

What I claim, therefore, and desire to secure by Letters Patent is 1. A tandem offset disk harrow comprising a front gang and a rear gang pivotally connected for relative angular movement, an angle adjusting member movably supported on the front gang, means for locking said member intermediate its ends to the front gang, and means connecting the ends of said member to the rear gang whereby any tendency for relative rotation of the gangs in one direction is resisted by that portion of the member between one end and said locking means acting in tension, and any tendency for relative rotation of the gangs in the other direction is resisted by that portion of the member between the ,other end and said looking means acting in tension.

2. A disk harrow comprising two pivotally connected angularly adjustable disk gangs, an angle adjusting member supported on one gang for movement relative thereto about a point coincident with the point of pivotal connection of the two gangs, means for locking said member against such movement, means connecting one end of said member with the other gang, said means acting to resist relative clockwise rotation of said gangs while offering no resistance to counter-clockwise rotation of said an and means connecting the other end said member with said other gang, said latter means acting to resist relative counter-clockwise rotation of said gangs while offering no resistance to clockwise rotation.

3. A disk harrow comprising two pivotally connected angularly adjustable disk gangs, an angle adjusting member, means for releasably locking said member to one gang along its length intermediate the ends, means connecting one end of said member with the other gang, said means acting to resist relative clockwise rotation of said gangs while offering no resistance to counter-clockwise rotation of said gangs, and means connecting the other end of said member with said other gang, said latter means acting to resist relative counter-clockwise rotation of said gangs while offering no resistance to clockwise rotation whereby said gangs are held against relative rotation in either direction by that portion of the member on one or the other side of said locking means acting in tension.

4.. A disk harrow comprising two pivotally connected angularly adjustable disk gangs, an arcuate shaped angle adjusting member supported on one gang for rotative movement about the center of curvature of the member, means for locking said member at selected points along its length, and two separate spaced connections connecting said member with the other gang, one of said connections acting to resist relative clockwise rotation of said gangs while offering no resistance to counter-clockwise rotation, the other of said connections acting to resist relative counter-clockwise rotation of said gangs while offering no resistance to clockwise rotation.

5. A disk harrow comprising two pivotally connected angularly adjustable disk gangs, an angle adjusting member supported for movement relative to one gang, means for releasably locking said member against movement relative to said gang, and means connecting said member to the other gang including two separate spaced connections, each connection including a bolt and an element having a slot into which said bolt extends, relative rotation of said gangs in one direction being resisted by the bolt of one connection bearing against the end of its slot and relative rotation of said gangs in the other direction being resisted by the bolt of the other connection b aring against the end of its slot.

6. In a tandem offset disk harrow, the combination of a front gang, a rear gang, a disk supporting frame for each gan said frames being pivotally connected toget er to permit relative angular adjustment thereof, and an angle adjusting member between the gangs and comprising an arcuate member supported on one frame and connected with the other frame through connections capable of placlng'said member under stress in tension only, and a latching device mounted on said one frame and adapted to engage the arcuate member to lock the gangs in angled position.

7. In a tandem offset disk harrow, the combination of a front gang, a rear gang, a disk supporting frame for each gang, said frames bemg pivotally connected together to permit relatlve angular adjustment thereof, and an arcuate angle adjusting member having a slot adjacent each end thereof, a bolt extending through each slot and fixed to a member of the disk supporting frame of the rear gang, said bolts and slots being so positioned that the contact ofone bolt with the rear end of ts slot prevents the other bolt from contactmg the forward end of it slot, and a latching device mounted on one of the frames and adapted to engage the arcuate member to lock the gangs in operating and transport positions.

8. In a tandem ofi'set disk harrow, the combination of a front gang, a rear gang, a dlSk supporting frame for each gang, said frames being pivotally connected together to permit relative angular adjustment thereof, and an arcuate angle adjusting member having a slot adjacent each end thereof, a bolt extending through each slot and through a member of the disk supporting frame of the rear gang, said bolts and slots being so positioned that the contact of one bolt with the rear end of its slot prevents the other bolt from contacting the forward end of its slot, a plurality of stirrups secured to the disk supporting frame of the front gang and arranged to slidingly support the arcuate member, a plurality of holes adjacent one end of the arcuate member, a latching device supported on the frame of the front gang and positioned so as to selectively engage the oles in the arcuate member to adjust the relative angle on the gangs, and a slot in the arcuate member adapted to engage with the latching device when the gangs are adjusted for transport.

9. In a tandem offset disk harrow, the combination of a front gang, a rear gang, a disk supporting frame for each gang, said frames being pivotally connected to permit relative angular adjustment thereof, and a tension draft device comprising an arcuate member having a slot adjacent each end thereof, a bolt extending through each slot and through a member of the disk supporting frame of the rear gang, a plurality of stirrups secured to the disk supporting frame of the front gang and arranged to slidingly support the arcuate member, a roller supported in each stirrup and having a rolling contact with the inner edge of the arcuate member, a plurality of spaced holes adjacent one end of the arcuate member, a latching device supported on the frame of the front gang and positioned so as to selectively engage the spaced holes in the arcuate member to adjust the relative angle of the gangs, and a slot in the arcuate member adapted to engage with the latching devlce when the gangs are adjusted for transport.

EDWARD C. BOPF. 

